High-pressure, high-strain-rate lattice response of shocked materials

DANIEL H. KALANTAR; J. BELAK; E. BRINGA; K. BUDIL; M. CATURLA

PHYSICS OF PLASMAS

AMER INST PHYSICS

Lugar: American Institute of Physics; Año: 2003 vol. 10 p. 1569 - 1576

1070-664X

Laser-based shock experiments have been conducted in thin Si and Cu crystals at pressures above the published Hugoniot Elastic Limit (HEL) for these materials. In situ x-ray diffraction has been used to directly measure the response of the shocked lattice during shock loading. Static film and x-ray streak cameras recorded x rays diffracted from lattice planes both parallel and perpendicular to the shock direction. In addition, experiments were conducted using a wide-angle detector to record x rays diffracted from multiple lattice planes simultaneously. These data showed uniaxial compression of Si (100) along the shock direction and three-dimensional compression of Cu (100). In the case of the Si diffraction, there was a multiple wave structure observed. This is evaluated to determine whether there is a phase transition occurring on the time scale of the experiments, or the HEL is much higher than previously reported. Results of the measurements are presented